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-2021
-I
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1. (1)
(ii) :
(iii) p2 + q2 = 20 2p + q = 8 , p q
2. (i) 3 24 6
(ii) 1 + 1/2 + 1/4 + 1/8 1/512
(iii) n
-
3. (i) y = 5x - 7 2y = 10x + 5
(ii) (1, 3, 5)
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Easy2Siksha.com
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5. (1)
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6. (i)
(ii) x = 2
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7. (i) (7x - 8)4 (5x - 1)3 x
(ii) wrtx
(iii) wr.tx
Easy2Siksha.com
8. (i) p = 50 - 3q , p = 5
(ii) = p = 50 - 3x p = 5
(iii) C = 60 - 12q + 2q2 , AC, MC AC
= (MC - AC)
-2021
-I
: :100
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1. (1)
(ii) :
(iii) p2 + q2 = 20 2p + q = 8 , p q
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1:
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• = 1/z
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• + = 9 … (i)
Easy2Siksha.com
• + = 11 … (ii)
• + = 10 … (iii)
2:
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! - (ii) (iii) A + C , -
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• + = 10
Easy2Siksha.com
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• + = 11 (2)
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= 1/ = 4 → = 1/4 = 1/ = 5 → = 1/5 = 1/ = 7 → = 1/7
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• xy / (x + y) = (1/4 * 1/5) / (1/4 + 1/5)= (1/20) / (9/20) = 1/9
• xz / (x + z) = (1/4 * 1/7) / (1/4 + 1/7)= (1/28) / (11/28) = 1/11
• zx / (z + x) = (1/7 * 1/4) / (1/7 + 1/4)= (1/28) / (11/28) = 1/11
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1: √x = a
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:
a :
2:
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√x = 4x = 16
√x = 2 = 4
: x = 4 x = 16
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(p) (q)
1: (2) :
2+=8=8−2(3)2
(1) :
p2+(8−2p)2=20p2 + (8 - 2p)2 = 20p2+(8−2p)2=20
(8 – 2p)² :
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2:
:
:
q :
1. p = 4.4:
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2. (i) 3 24 6
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1: 3 24 6
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6 :
• : a+d=3+3=6
• : 3+23=9
• : 3+33=12
• 5 : 3+43=15
• : 3+53=18
• 7 : 3+63=21
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3, 6, 9, 12, 15, 18, 21, 24
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Easy2Siksha.com
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512 2 :
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−1=9=10
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GP nnn :
Easy2Siksha.com
, nnn :
n :
• n = 1 :
1=2(1−1/2)=2(1/2)=1
• n = 2 :
2=2(1−1/4)=2(3/4)=1.5
• n = 3 :
3=2(1−1/8)=2(7/8)=1.75
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10
Easy2Siksha.com
-
3. (i) y = 5x - 7 2y = 10x + 5
(ii) (1, 3, 5)
9
(ii)
:
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1
100
2
50
3
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(i): y = 5x - 7 2y = 10x + 5
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:
y=5x−7y = 5x - 7y=5x−7
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Easy2Siksha.com
y=+
, m=5m = 5m=5
2:
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2y=10x+5
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1: 2 :
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3 :
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Easy2Siksha.com
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Easy2Siksha.com
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y=5x−7y = 5x - 7y=5x−7 2y=10x+52y = 10x + 52y=10x+5
= 5.
Easy2Siksha.com
2. 3D , 9 : :
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Easy2Siksha.com
3. :
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5. :
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U
Easy2Siksha.com
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U = ≤ 10, U = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
10. :
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A , B
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4. (A Δ B)
A B , : A Δ B = (A –
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:
= {1, 2, 3}, = {3, 4, 5} Δ = {1, 2, 4, 5}
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70 :
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Easy2Siksha.com
2.
1:
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• M =
• S =
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n(M – S) = 20 (n(M)) = 30
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n(M ∩ S) = n(M) – n(M – S)= 30 – 20 = 10
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n(S) = x
Easy2Siksha.com
:
() = 70 = 30 + x–10=> 70 = 20 + x=> x = 50
, = 50
: = n(S – M) = n(S) – n(M ∩ S)= 50 – 10 = 40
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1. = 10
2. = 40
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f(x)=2x+3f
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Easy2Siksha.com
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Easy2Siksha.com
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8. (i) p = 50 - 3q , p = 5
(ii) = p = 50 - 3x p = 5
(iii) C = 60 - 12q + 2q2 , AC, MC AC
= (MC - AC)
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Easy2Siksha.com
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Easy2Siksha.com
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Easy2Siksha.com
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